Author Notes: It took a brilliant, adventurous chemist to discover the simplest way to make chocolate mousse at home. Hervé This, the father of molecular gastronomy, discovered how to make a flawless, creamy chocolate mousse out of just chocolate and water.

This all happens fast as the mixture cools, so chances are you'll go too far on your first try. Don't worry — just return it to the pan, melt it, and start over (see step 3). Once you have the rhythm down, you can flavor it as you wish with liqueurs or coffee or spices, sweeten it to your liking, or just keep it dark and intense. In all of these scenarios, a little whipped cream up top is never a bad idea. Adapted from Molecular Gastronomy: Exploring the Science of Flavor (Columbia University Press, 2008) - Genius Recipes

Simply pour water into a saucepan (which will be improved from the gastronomic point of view if it is flavored with orange juice, for example, or cassis puree). Then, over medium-low heat, whisk in the chocolate. The result is a homogenous sauce.

Put the saucepan in a bowl partly filled with ice cubes (or pour into another bowl over the ice -- it will chill faster), then whisk the chocolate sauce, either manually with a whisk or with an electric mixer (if using an electric mixer, watch closely -- it will thicken faster). Whisking creates large air bubbles in the sauce, which steadily thickens. After a while strands of chocolate form inside the loops of the whisk. Pour or spoon immediately into ramekins, small bowls or jars and let set.

Note: Three things can go wrong. Here's how to fix them. If your chocolate doesn't contain enough fat, melt the mixture again, add some chocolate, and then whisk it again. If the mousse is not light enough, melt the mixture again, add some water, and whisk it once more. If you whisk it too much, so that it becomes grainy, this means that the foam has turned into an emulsion. In that case simply melt the mixture and whisk it again, adding nothing.

Not sure what i did wrong. Perhaps I didn't have enough fat or didn't whisk long enough. But after refrigerating ours turned out quite thick. My girlfriend described it as "fudgy". We still thought it was yummy and devoured them.

So easy! and it takes just a few moments of whisking for the chocolate to begin setting. I flavored it with a few drops of orange essential oil and will serve it with lightly sweetened whipped cream. My house was pretty warm today and the mousse began to "unsettle" after a few moments in the ramekins, so next time I'll prechill the containers and get them into the refrigerator more quickly. Pity the poor person who has to lick the bowl, the beaters, the spatula, her fingers...

My one issue, though, is that I often end up with mousse that tastes too fruity. You must use high-quality chocolate, but it takes a bit of luck and careful consideration to find the best one for this mousse... I think one that has more "creamy" and "coffee" notes, without any sharp angles in the flavor. Honestly, one of the best ones I've found is the Trader Joe's Pound Plus dark chocolate because it seems to have a very smooth, "chocolatey" flavor.

We haven't tried it but it might work. I would use high quality white chocolate with a good amount of cocoa butter. Let us know if you try it! You might also want to try this: http://food52.com/recipes...

I'm interested in this and will probably try it, but to be perfectly honest it sounds too rich to me. Julia Child's mousse is too rich for me, so I imagine this would be over the top; however, having said that, I make a chocolate torte from Lora Brody, which is delicious and very rich - not to be eaten without whipped cream - and I love it.

I saw this recipe last night and decided to try it. I didn't think it would work because I am in Jamaica and my kitchen tends to be warmer than most. I thought the bowl of ice wouldn't be enough to cool the chocolate, so I threw my metal bowl in the freezer for awhile just to ensure I could maintain a certain temperature. It came out perfectly. I substituted half of the water with amaretto liqueur and topped with whipped cream and a dash of cinnamon. Talk about death by chocolate....My family and I are sold and ready to experiment with different liqueurs and toppings. Thank you Thank you Thank you....from a true chocoholic

Never dreamed this would work, but, wow, did it ever! Replaced 1 1/2 - 2 TB of the water with Navan Liqueur and followed directions for melting. Began whisking by hand and, although it really didn't take long to thicken up, I thought my arm would fall off! Wasn't quite sure when to stop, apparently it was just long enough. Served with sweetened whipped cream to which I added more Navan............Ymmmmm!!!

I made it for a Valentine's Day treat for my husband and 2.5 year old son! I used 62% Cacao Semisweet Chocolate from Scharffen Berger, whisked until the chocolate suddenly went thick and light (it took just a few minutes with an electric whisk), scraped it into ramekins and put them to chill in the fridge. I regretted the latter step, I have to say, chilling the mousse even for 30 minutes or so hardened it. It was still delicious, especially with vanilla whipped cream, but it was nicest at room temperature immediately after I made it. My husband and son

I made this today too. But, it was a bit of a disappointment...Made at about 4pm and served about 7pm - hard as a rock. Bummer. I did garnish with whipped cream and a few slices of fresh strawberries.
I'm going to try again, but next time I will a) use a less intense dark chocolate (used Trader Joe's 85% Dark - too bitter) and b) serve shortly after I make it.
I love the simplicity of the dessert, but I think I could have used more detail in the directions.

I made this today for my wife. I used straight water and an electric mixer. Richest mousse I've ever had. I made it at 3:00 and ate it at 7:00 it had "set up" but the air bubbles kept it from getting too hard. I'd say eat within an hour of finishing the whipping for best results. We made 4 servings, I'm a big guy and had to force myself to finish it. The chocolate was intense, rich, I felt like I was about to enter a diabetic coma when I'd finished. Yes I'd made whip cream to top, it was too rich without the cream on top.

Well I couldn't believe this would work but in the interests of science :) decided to give it a try. Only made half the recipe as I plan on eating it all myself. SO EASY! I almost skipped supper but I'm fixing that now & will eat this after. It's in the fridge but I did lick the beaters. Once it was in the ice bath I used an electric hand beater & it took about another 3-4 mins, but you can stop at any time as soon as it's stiff enough for your liking.

Instead of stevia (which I find has a whang to it) or diet sweeteners (which have nasty chemicals and subvert your desire to lose weight), may I suggest blue agave syrup, which is delicious, low on the glycemic index, and safe for diabetics; it doesn't take much. You can buy it at Costco.

Why are you all making this so complicated? Put the water in a pot over medium heat, add the unmelted</> chocolate, and stir till it's melted and makes a smooth sauce. Ice bath, whisk, and poof! Mousse!

I used Scharffen Berger 68% that I treated myself to at Xmas, and have been saving for a special occasion. Not being much of a hand-whisker, I used the number 1 setting (lowest) on my KA stick blender, using the whisk attachment, adding 1 Tbs. sugar & a splash of Kahlua. Yummers! Refrigerating now & going to be V Day dessert tonight! Thank you!!!

Amen RJ!!!!!! The water keeps the chocolate from burning--particularly if you use a medium low burner setting. A little stir every once in awhile and in 5-6 minutes viola--melted chocolate ready for the ice bath and mixer.

This recipe is outrageously simple and delicious! Added a shot of grand marnier and a dash of salt and am looking forward to earning major husband points when I break this dish out on Valentine's Day/ Thanks Genius Recipes!

Genius?? this?? Its WAAAY beyond that, its sheer madness, insanity.. (evident by the way its making me Rave.. n'est ce pas??), I whipped up some with left over chocolate from making truffles, with some caramelized pineapple & topped with grains of Thai ginger salt..

Thanks Kristen for this great recipe. However, I would like to modify it for diabetics by using 100% unsweetened chocolate and then sweeten it using erythritol and/or stevia. Anyone know how to do that?

I generally use xylitol for my sugar- free cooking and baking, now. It measures 1:1 for sugar, tastes, and behaves like sugar. It's also diabetic-safe. I suggest adding it in during the initial cooking stage, to your taste, then proceed with the rest of the procedure.

I wonder whether this same procedure would work for white chocolate? Also, I have some Taza chocolate Mexicana, which does not have lecithin but has intense flavor and less sugar. I wonder whether there's an ingredient (other than cream) that would provide the emulsifying element?

I just made this, it took about 5 minutes and is impossibly delicious. I even hand-whisked which I almost never do as it is usually a pain. I used Guittard bittersweet chocolate wafers. This is definitely going in the "greatest hits" roster. Thank you so much!!!

In response to the heat questions below - As a retired chocolatier, I've been making chocolates for years. Now that I no longer have big, fancy machines to melt and temper my chocolate for me, when I need to melt chocolate I use (gasp) the microwave!

I melt on 30% power setting in sessions of .5 - 3 minutes. 3 to get going (if over a lb. of chocolate) and then shorter and shorter. Melt, remove bowl, wait a 1 minute or so, stir and repeat until all is melted. Remember, working (dark) chocolate temperature, when tempered, is about 89* +/-, depending on the chocolate so the temperature does not need to be very high. 89* chocolate will feel cool if touched to your skin just below your lower lip.

Chocolate can be deceptive when it is in the microwave. It does not necessarily lose its form, which is why it's important to remove it and stir. Also - Check that the bowl you are melting in is truly microwave safe. Some glass bowls really heat up and continue to warm the chocolate, another reason why the stirring and waiting is important.

When you remove the chocolate from the microwave, give several good long stirs. Spread that heat and melt around. At the beginning, you want to coat the un-melted bits with the melted bits, to really get things going and make sure you have even heat. Hot spots are bad, bad, bad.

Be sure to use a thermometer! I use an infrared one. Its worth its weight in gold, in my opinion. But a glass or an instant read one works just as well. If you want to be sure that all of the crystals in chocolate have well and truly melted, shoot for between 115* and 120* but NOT OVER 120*. If you have accidentally crept over 120* then stir, stir, stir, to cool down and you can probably save the chocolate.

For this recipe, where the chocolate and water are heated together, you will likely get best results with well chopped chocolate, even if it is already in "discos". Just heat in the microwave, as above, until all is melted and smooth. Stir in a small circle in the middle, with the whisk, until emulsification starts (begins to look like mayonnaise) and then expand to bring in more and more until all is emulsified and homogeneous.

Thanks for asking! I just clarified the recipe. Honestly, This doesn't go into much detail, but the recipe is so forgiving that it doesn't matter. I just made sure not to crank it up high enough to burn the chocolate before it melts.